The March PRRI/RNS Religion News Survey showed that a slim majority (52%) of Americans favor allowing gay and lesbian couples to marry legally, while 44% are opposed. There are large gaps on this issue by age, gender, party affiliation, and religious affiliation. Nearly three-quarters (74%) of Millennials (age 18-29) support same-sex marriage, compared to only one-third (33%) of seniors.

There are religious groups on both sides of the same-sex marriage debate. Strong majorities of Jews (81%) and the religiously unaffiliated (77%) support same-sex marriage, in addition to nearly 6-in-10 (59%) Catholics and a solid majority (56%) of white mainline Protestants. Minority Christians are more divided, with 50% opposed to same-sex marriage and 43% in favor. White evangelical Protestants are strongly opposed to same-sex marriage, with over three-quarters (77%) in opposition to allowing gay and lesbian couples to marry legally.

Women are significantly more likely than men to support same-sex marriage. A solid majority (58%) of women favor allowing gay and lesbian couples to marry legally, while fewer than 4-in-10 (37%) are opposed. Men are more divided (45% in favor, 49% opposed).

Majorities of Democrats (64%) and Independents (55%) support legalizing same-sex marriage. Republicans, by contrast, are strongly opposed to same-sex marriage, with 33% in favor and 62% opposed.

There are some racial differences on this issue. A slim majority (53%) of white Americans favor same-sex marriage, while 43% remain opposed. By contrast, a slim majority (51%) of black Americans oppose same-sex marriage, while 45% support it.

Public support for same-sex marriage has steadily increased over the past five years. In January 2006, support hovered around 40%. In early 2011, several public opinion research organizations, including Public Religion Research Institute, found majority support for same-sex marriage.